Process for manufacturing nitric acid by means of superheating, &amp;c.



No. 882,958. PATENTED MAR. 24, 1908.

H. PAULING.

PROCESS FOR MANUPAOTURING'NITRIG ACID BY MEANS OF SUPERHEATING, &0.

APPLIGAIION FILED AUG.12, 1902v UNITED STATES PiX TENT OFFICE HARRY PAULING, OF BRANDAU, AUSTRIA-HUNGARY, ASSIGNOR TO WES'lTDlJUlTSCl-IE THOMASIHOSPHAT-WERKE G. M. B. 11., Ol liERLIN, GERMANY.

PROCESS FOR MANUFACTURING NITRIC ACID BY MEANS OF SUPEBHEATING, 800.

Specification of Letters Patent.

Patented March 24, 1908.

Application filed August 12, 1902. Serial No. 119,393.

T 0 all whom it may concern:

Be it known thatI, HARRY PAULING, director of mines, a citizen of the Kingdom of Saxony, andresident of Brandau, Bohemia,

Austria-Hungary, (whose post-office address is house No. 200,) have invented certain new and usefullmprovements in Processes for Manufacturing Nitric Acid by Means of Superheating, &c., of which the following is a specification.

My invention relates to a process for the manufacture of nitric acid from a moist mixture of nitrogen and oxygen, such, for instance, as atmospheric air. This is efiected by heating the gas mixture up to the oxidation point of nitrogen ina suitable furnace,

then repeatedly assing said mixture through regenerators ant? then introducing steam into the furnace, said steam taking part in the reaction.

When a mixture of nitrogen and oxygen is heated u to the tem erature, above named, the nitrogen as is we 1 known by experience simply burns like any other gas mixed with oxygen and heated to the proper temperature. The product obtained may be converted into nitric acid by mixing it at a high tem erature with steam.

h ow the process of heating the gas mixture may be advantageously erformed in a re generating furnace provi ed with means for heating the mixture, which is repeatedly blown or sucked through said furnace in the usual manner by the aid of a chimney or a blower provided with suitable reversible valves. Of all the meansfor heating gases to a high temperature the electric arc is by far the most convenient. I have therefore constructeda regenerating furnace containing a heating chamber and one or more pairs of heat regenerators surrounding said 'cham ber, the heating. chamber containing one or more airs of electrodes connected with a suitab e source of electricity, to produceone or more electric arcs in said heating chamber.

The accompanying drawings show diagrammatically a furnace of this description.

Referring to said drawing a designates the wall of the furnace, b is the heating chamber; (l and c are two pairs of heat regenerators. e e are the electrodesarranged in the heating chamber. ff are the channels conducting the gas mixture from the regenerators to the heating chamber and vice versa.

'erators and the heating chamber.

. regenerators.

g g are the openings for either introducing or extracting the gas mixture and for blowing and sucking said mixture through the regenlnto this furnace, or one of any other suitable form, a current of air is blown or sucked, and after passing through one pair of regenerators the air will enter the heating chamber and in passing through the electric arcs formed be tween the electrodes arranged in said cha1nber will pass into the second pair of regenerators. Before the heated alr has reached the corresponding opening of the furnace,

the valves are reversed and the heated air now passes again through the heating chamber in an opposite direction. An increase of temperature will take place every time the current of air is reversed, and after a certain number of reversions the temperature withtion-point of nitrogen. At this point the electric current maybe interrupted and the electrodes projecting through the walls of the heating chamber pulled out so far that their points do not longer project into the chamber. Then an air current is blown or sucked through the furnace, and upon entering the first pair of regenerators takes up a certain amount of the heat stored in these It then passes through the heating chamber into the second pair of re generators, storing there part of the heat received, and, after reversing the valves, re-

turning through the heating chamber into the firstpair of regenerators, and so on, until all the nitrogen contained in this air has been burned. Now steam is blown into the furnace and the nitric acid formed is extracted. The heating chamber having by this time lost part of the heat accumulated in it, the electrodes are pushed back into it and after closing the circuit the electric arcs are formed as before, and the whole process is gone through again in the same manner. a

It is evident that the above-described process may be carried out by the employment of other forms ofapparatus than that herein shown and described.

What I claim as new is:

1. The

taining nitrogen and oxygen to the oxidation-point of nitrogen, cooling said mixture and storing the heat, and transferring the process of oxidizing nitrogen, I which consists in heating a gas-mixture conin the heating chamber will rise to the oxidastored heat to a fresh mixture 'of nitrogen and oxygen. c

2. The process of manufacturing nitric acid, Which consists in heating a gas-mixtureheat to a fresh mixture ofrnitrogen and oxy-- gen, and adding steam to convert the gaseous product into nitric-acid.

3. The process of oxidizing nitrogen, which consists in heating the surfaces of a plurality of refractory bodies to a high tem perature, and heating agas-mixture contain- 1ng nitrogen and oxygen to the oxidationtemperature, discontinuing the supply of 2 heat, "and introducing into said chamber a gas-mixture containing nitrogen and oxygen and thereby heating the mixture to the oxi elation-point of nitrogen.

In testimony whereof I afiix my signature 5 in presence of two Witnesses.

HARRY PAULING. Witnesses:

HENRY HAsPER,

WOLDEMAR HAUPT. 

